GPS navigation systems include use of a constellation of satellites each of which provides a coded signal which may be picked up by radio receivers in close proximity to the earth. Separate coded signals from a set of satellites may be processed by a receiver for use in determining location as defined by latitude and longitude based upon the code carried by the signals. The operation of the GPS receiver in determining location based on coded signals received from satellites reflects the conventional functioning of such systems.
During the course of time, alternative uses of the GPS satellite system have been developed by various users. One such use of GPS signals is in determining ones spatial orientation as described in U.S. Pat. No. 5,021,792, issued to one of the inventors of the present application, and incorporated herein by reference. The spatial orientation system of the '792 patent requires the use of multiple receivers and is based upon mathematical derivations of phase measurements of the carrier signal.
Although the above referenced spatial orientation system works well as described, it requires the use of duplicative hardware, such as receivers and antenna and the associated control devices for enabling and orchestrating such a system.
Accordingly, it has long been the goal of numerous entities to develop and refine secondary uses for the GPS system that minimize hardware requirements, preferably operable from a single GPS receiver.